Quadrantes Claudian

Chemical Compositions of Copper-Based Roman Coins Claudian Quadrantes A.D. 41-42... 

The density of pure copper is 8.93 g/cm, and the densities of the Claudian quadrantes average about 8.91 0.04 g/cm. None of the coins has any appreciable quantity of voids or internal pores. Die orientations were determined by rotating each coin about its obverse vertical axis. The reverse vertical axis was then found to point in a given direction, which was identified by the equivalent direction of the hour hand of a clock. All of the 84 Claudian quadrantes in the chemical compositional group. 

No significant differences in size or physical properties could be correlated with catalog numbers of the quadrantes. Figure 1 illustrates the different varieties of Claudian quadrantes, namely BMC [British Museum Catalog number (J5)] 174, 179, 181, 182, and 182 variety. 

Ninety-nine Claudian quadrantes made in a.d. 41 or 42 were analyzed for several elements (approximate standard deviations are in parenthe-... 

Figure 1. Claudian quadrantes magnification is 2X BMC, British Museum Catalog (15). Coin no. 1164 is the only coin from compositional group 41 A. All other coins are from group 41 B. BMC 182 variety is the same as BMC 182 except PP is omitted from its reverse legend. Continued on next page.

Table II summarizes previous analyses and compares them with the present two compositional groups 41 A and 41 B (the quadrantes made in a.d. 42 all belong to the cbmpositional group 41 B). Nine Claudian asses, which are large-diameter coins of nearly pure copper, have been analyzed (9), and the analyses are very close to the compositions of the group 41 B coins. Four of the asses were minted in a.d. 41, and five in a.d. 42.

Table II. Comparison of Compositions of Claudian Quadrantes with Compositions of Tiberian, Caligulan,...

Seven previously analyzed Claudian quadrantes (9) are fairly close in composition to the ones reported in this chapter. However, improved analytical techniques and use of a better x-ray fluorescence spectrometer for nickel, silver, and lead analyses have produced results that are probably more accurate than the previous ones. 

The Claudian quadrantes group 41 A (thick flans) have nearly the same composition as the imitation Claudian asses. The primary difference is in silver concentration, but the difference is large enough to indicate that there is probably no connection between Claudian imitation asses and group 41 A quadrantes. 

Fourteen Tiberian asses dating from a.d. 34-37 have been analyzed (9). These coins are different in trace element composition from either group 41 A or 41 B (Table II). For instance, the Tiberian asses have significantly higher silver contents and usually more antimony and less lead than group 41 A coins. The Tiberian asses are quite different from the group 41 B Claudian quadrantes. 

The chemical analyses and physical properties of Claudian quadrantes raise several questions for future study ... 

Why are there two major compositional groupings of Claudian quadrantes ... 

Dimensions and Physical Properties of Claudian Quadrantes—Continued... 

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